body {
    margin: 0;
    padding: 0;
    font-family: Arial, sans-serif;
}
.body {
    margin-bottom: 60px; /* 空出导航栏的空间 */
}
ul {
    list-style-type: none;
    padding: 0;
    margin: 0;
}
li {
    padding: 10px;
    border-bottom: 1px dotted black;
}
.navbar {
    position: fixed;
    left: 0;
    bottom: 0;
    width: 100%;
    overflow: hidden;
}